Labelling the Triangle
Completion requirements
Lesson 1: Pythagorean Theorem - Labelling the Triangle
Constructing Knowledge
The first step in solving for a missing side length on a right angle triangle is to label the sides of the triangle. Labelling the sides allows for correct substitution into the formula.
The vertices of a triangle, which also relate to the triangle's interior angles, are labelled with uppercase letters.
Triangle side length labels are placed about halfway along a side, and are labelled with the lowercase letter of the opposite vertex.
In the formula a2 + b2 = c2, side c corresponds to the hypotenuse. As such, the vertex at the right angle of the triangle is labelled C.
The vertices of a triangle, which also relate to the triangle's interior angles, are labelled with uppercase letters.
Triangle side length labels are placed about halfway along a side, and are labelled with the lowercase letter of the opposite vertex.
In the formula a2 + b2 = c2, side c corresponds to the hypotenuse. As such, the vertex at the right angle of the triangle is labelled C.
Multimedia
A video describing how to label a triangle diagram for the Pythagorean Theorem is provided.
EXAMPLE 1
Label the sides of the triangle shown below.
Solution
x - the side (hypotenuse) opposite the right angle X.
z - the side opposite acute angle Z.
y - the side opposite acute angle Y.
Now, it is your turn! Complete the questions in your Chapter 3, Lesson 1 Practice Makes Perfect that refer to Labelling the Triangle.
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